Evaluation of the efficacy of magnesium sulphate as an adjuvant to lignocaine for intravenous regional anaesthesia for upper limb surgery.

Several additives have been combined with local anaesthetics for intravenous regional anaesthesia to improve block quality, analgesia and to decrease tourniquet pain. Magnesium sulphate is one potential additive. This prospective, randomised, double-blinded study was conducted in 30 ASA physical status I or II patients undergoing upper limb surgery under tourniquet. In group L, patients received intravenous regional anaesthesia with lignocaine alone (9 ml of 2% lignocaine diluted with normal saline to total volume of 36 ml). Patients in group M received intravenous regional anaesthesia with lignocaine plus magnesium sulphate (6 ml of 25% magnesium sulphate plus 9 ml of 2% lignocaine diluted with normal saline to total volume of 36 ml). Assessment was by observing the response to injection of drug; sensory and motor block and tourniquet pain. The mean time of onset of sensory block was 12.40 and 3.47 minutes in groups L and M respectively (P < 0.001). The average times of onset of motor block in groups L and M were 17 and six minutes respectively (P < 0.001). Of the patients in group M, 66.7% reported moderate to severe pain while the drug was being injected, compared to 20% in group L (P=0.011). There was a statistically significant difference in visual analogue scale for tourniquet pain at 10 and 30 minutes after tourniquet inflation (lower in group M). These findings indicate that magnesium sulphate added as an adjuvant to lignocaine hastens the onset of sensory and motor block and decreases tourniquet pain. However there is increased incidence of transient pain on injection if magnesium sulphate is added.

A complete complementary DNA for the oncodevelopmental calcium-binding protein, oncomodulin.

RNA from a rat liver tumor (Morris hepatoma 5123tc) was used to construct cDNAs together comprising the complete coding sequence of rat oncomodulin mRNA. Information obtained from these cDNAs as well as from primer extension analysis gave a deduced length for the complete oncomodulin mRNA of approximately 680 nucleotides (excluding the poly(A) tail) including a 5'-untranslated region of 97 +/- 2 nucleotides, a 324-nucleotide-coding sequence and a 259-nucleotide 3'-noncoding region. Comparison of the oncomodulin cDNA sequence with those coding for other members of the calcium-binding protein family shows little homology with the exception of a recently reported parvalbumin cDNA where the oncomodulin and parvalbumin nucleotide sequences are 59% identical in the protein-coding region. RNA blot analysis of poly(A+) RNA from normal adult rat liver gave no evidence of oncomodulin expression in this tissue. A single RNA species was detected, however, in RNA extracts from the hepatoma and from rat and human placentas. A probe prepared from one of the rat oncomodulin cDNAs hybridized with a single DNA species in restriction digests of hepatoma and normal DNA from rat and sequences in DNA of humans and other mammals. A 38-nucleotide sequence spanning the 5'-untranslated region and the first seven codons of the oncomodulin cDNA, was far less homologous than was the same region of a parvalbumin cDNA, to a chicken calmodulin cDNA sequence coding for the first calcium-binding domain. The oncomodulin gene appears to have diverged more from that of calmodulin than has the parvalbumin gene.